Package org.codehaus.groovy.util

## Class ListHashMap<K,​V>

- java.lang.Object
- - org.codehaus.groovy.util.ListHashMap<K,​V>

- All Implemented Interfaces:
    `Map<K,​V>`

      public class ListHashMap<K,​V>
      extends Object
      implements Map<K,​V>

  This class represents a `Map` that is optimized for a small number of entries. For a number of entries up to `listSize` the entries are stored in arrays. After `listSize` entries are exceeded storage switches internally to a `Map` and converts back to being array based when its size is less than or equal to `listSize`. Null keys or values are not supported. This class is not thread safe.

- - ### Nested Class Summary

    - ### Nested classes/interfaces inherited from interface java.util.Map

      `Map.Entry<K extends Object,​V extends Object>`

  - ### Constructor Summary

    Constructors
    Constructor | Description
    --- | ---
    `ListHashMap()` |
    `ListHashMap​(int listSize)` |

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `void` | `clear()` |
    `boolean` | `containsKey​(Object key)` |
    `boolean` | `containsValue​(Object value)` |
    `Set<Map.Entry<K,​V>>` | `entrySet()` |
    `V` | `get​(Object key)` |
    `boolean` | `isEmpty()` |
    `Set<K>` | `keySet()` |
    `V` | `put​(K key, V value)` |
    `void` | `putAll​(Map<? extends K,​? extends V> m)` |
    `V` | `remove​(Object key)` |
    `int` | `size()` |
    `Collection<V>` | `values()` |

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

    - ### Methods inherited from interface java.util.Map

      `compute, computeIfAbsent, computeIfPresent, equals, forEach, getOrDefault, hashCode, merge, putIfAbsent, remove, replace, replace, replaceAll`

- - ### Constructor Detail

    - #### ListHashMap

          public ListHashMap()

    - #### ListHashMap

          public ListHashMap​(int listSize)

  - ### Method Detail

    - #### clear

          public void clear()

      Specified by:
        `clear` in interface `Map<K,​V>`

    - #### containsKey

          public boolean containsKey​(Object key)

      Specified by:
        `containsKey` in interface `Map<K,​V>`

    - #### containsValue

          public boolean containsValue​(Object value)

      Specified by:
        `containsValue` in interface `Map<K,​V>`

    - #### entrySet

          public Set<Map.Entry<K,​V>> entrySet()

      Specified by:
        `entrySet` in interface `Map<K,​V>`

    - #### get

          public V get​(Object key)

      Specified by:
        `get` in interface `Map<K,​V>`

    - #### isEmpty

          public boolean isEmpty()

      Specified by:
        `isEmpty` in interface `Map<K,​V>`

    - #### keySet

          public Set<K> keySet()

      Specified by:
        `keySet` in interface `Map<K,​V>`

    - #### put

          public V put​(K key,
                       V value)

      Specified by:
        `put` in interface `Map<K,​V>`

    - #### putAll

          public void putAll​(Map<? extends K,​? extends V> m)

      Specified by:
        `putAll` in interface `Map<K,​V>`

    - #### remove

          public V remove​(Object key)

      Specified by:
        `remove` in interface `Map<K,​V>`

    - #### size

          public int size()

      Specified by:
        `size` in interface `Map<K,​V>`

    - #### values

          public Collection<V> values()

      Specified by:
        `values` in interface `Map<K,​V>`